WO2007024473A1 - Formation d'image couleur sur un dispositif d'affichage - Google Patents

Formation d'image couleur sur un dispositif d'affichage Download PDF

Info

Publication number
WO2007024473A1
WO2007024473A1 PCT/US2006/030832 US2006030832W WO2007024473A1 WO 2007024473 A1 WO2007024473 A1 WO 2007024473A1 US 2006030832 W US2006030832 W US 2006030832W WO 2007024473 A1 WO2007024473 A1 WO 2007024473A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
modulator
liquid crystal
laser
layer
Prior art date
Application number
PCT/US2006/030832
Other languages
English (en)
Inventor
Erica Nicole Montbach
Keith Brian Kahen
Original Assignee
Eastman Kodak Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eastman Kodak Company filed Critical Eastman Kodak Company
Publication of WO2007024473A1 publication Critical patent/WO2007024473A1/fr

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G02B26/004—Optical devices or arrangements for the control of light using movable or deformable optical elements based on a displacement or a deformation of a fluid
    • G02B26/005—Optical devices or arrangements for the control of light using movable or deformable optical elements based on a displacement or a deformation of a fluid based on electrowetting
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/48—Laser speckle optics
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133603—Direct backlight with LEDs
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2203/00—Function characteristic
    • G02F2203/12—Function characteristic spatial light modulator
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2203/00—Function characteristic
    • G02F2203/34—Colour display without the use of colour mosaic filters

Definitions

  • the present invention relates to forming a color image using a light source and a modulator.
  • LCD liquid crystal display
  • a liquid crystal cell is placed between a pair of polarizers. Light that enters the display is polarized by the initial polarizer. As the light passes through the liquid crystal cell, the molecular orientation of the liquid crystal material affects the polarized light such that it either passes through the analyzer or it is blocked by the analyzer. The orientation of the liquid crystal molecules can be altered by applying a voltage across the cell, thus enabling varying amounts of light intensity to pass through the LCD pixels.
  • This switching energy is typically much less than that required for cathode ray tubes (CRT) employing cathodoluminescent materials, making a display that utilizes liquid crystal materials very attractive.
  • CTR cathode ray tubes
  • the typical liquid crystal cell contains a color filter array (CFA) comprised of red, green, and blue transmitting pixels.
  • CFA color filter array
  • BLU backlight unit
  • the transmission spectra of each of the CFA pixels must have a large full-width at half maximum (FWHM).
  • FWHM full-width at half maximum
  • the color gamut of the LCD is, at best, approximately 0.7 of the NTSC color gamut standard.
  • FWHM full-width at half maximum
  • LCDs are quickly replacing CRTs and other types of electronic displays for computer monitors, televisions, and other office and household displays.
  • LCD's suffer from poor contrast ratios at larger viewing angles. Unless the contrast ratio is improved at large viewing angles, the penetration of LCDs into certain markets will be limited.
  • the poor contrast ratio is typically due to increased brightness of the display's dark state.
  • LCDs are optimized such that the display has the highest contrast ratio within a narrow viewing cone centered on axis (at zero degrees viewing angle). As the display is viewed off-axis at larger viewing angles, the dark state experiences an increase in brightness, thus decreasing the contrast ratio. When viewing full color displays off axis, not only does the dark state increase in brightness, but also there is a shift in color of both the dark and bright states.
  • PL-LCD photoluminescent-LCD
  • This display employs a backlight unit of narrow band frequency, a liquid crystal modulator, and a photoluminescent output screen for producing color.
  • PL-LCD light source utilizes wavelengths that are in the UV, which would accelerate the breakdown of the liquid crystal materials. Also, the PL-LCD light source is much less efficient than the standard cold cathode fluorescent lamps (CCFLs) used in typical LCD displays.
  • CCFLs standard cold cathode fluorescent lamps
  • apparatus for forming a colored image on a display comprising: a) a VCSEL array device having a plurality of light-emitting pixels wherein each light-emitting pixel produces a beam of light including substantial components in a portion of the visible spectrum so that different light- emitting pixels produce different colored light; and b) a light shutter layer for each light-emitting pixel providing a modulator disposed in the path of the corresponding light beam for selectively passing corresponding colored light for providing a colored light image on the display.
  • a VCSEL array device having a plurality of light-emitting pixels wherein each light-emitting pixel produces a beam of light including substantial components in a portion of the visible spectrum so that different light- emitting pixels produce different colored light
  • a light shutter layer for each light-emitting pixel providing a modulator disposed in the path of the corresponding light beam for selectively passing corresponding colored light for providing a colored light image on the display.
  • a pixelated two- dimensional vertical cavity surface emitting laser (VCSEL) array as the light source for a display.
  • Each color element contains thousands of micron-sized laser pixels, which are mutually incoherent. This leads to each color element producing multimode laser light.
  • the pixel size being 3 to 5 microns in diameter, the divergence angle of the multimode laser light is on the order of 3-5°. This small divergence angle enables a 1 : 1 correspondence between the laser's color elements and a suitable optical switch.
  • Additional advantages of the present invention come from the light output from each color element being nearly single wavelength. This property results in a large enhancement of the color gamut of the display. In applications that prefer a limited viewing angle, such as for privacy viewing, the near collimation of the light source results in a much enhanced on-axis viewing brightness for the display compared to typical ones. This enhancement can either permit greatly increased display brightnesses or can be traded for greatly increased display power efficiency (enabling a large boost in the battery lifetime).
  • FIG. 2 shows a side cross sectional schematic of an optically pumped two-dimensional VCSEL array device
  • FIG. 3 shows a top view of a two-dimensional VCSEL array device containing red, green, and blue emitting elements in which each element is composed of thousands of micron-sized laser pixels;
  • FIG. 4 shows a side view of another embodiment of an optically pumped two-dimensional VCSEL array device which includes absorbing elements
  • FIG. 5 shows a side cross sectional view of another embodiment of an optically pumped two-dimensional VCSEL array device which includes dyed photoresist absorbing elements
  • FIG. 6 shows a side cross sectional view of another embodiment of an optically pumped two-dimensional VCSEL array device which includes planarized absorbing elements
  • FIG. 8 shows a side cross sectional view of another embodiment of an optically pumped two-dimensional VCSEL array device which includes an etched dielectric stack that has been planarized;
  • FIG. 9 is a schematic of the display device containing the VCSEL array device.
  • FIG. 10 is a schematic of a linear LED-array driven backlight unit pumping the VCSEL array device
  • FIG. 11 is a schematic of a planar LED-array driven backlight unit pumping the VCSEL array device
  • FIG. 12 is a schematic of a cold cathode fluorescent lamp driven backlight unit pumping the VCSEL array device
  • FIG. 13 is schematic of another embodiment of a cold cathode fluorescent lamp driven backlight unit pumping the VCSEL array device
  • FIG. 14 is a schematic of the liquid crystal cell and its components, including only the analyzer
  • FIG. 15 is a schematic of the liquid crystal cell and its components, including the polarizer and analyzer;
  • FIG. 16 is a schematic of a cholesteric liquid crystal cell, including layers for each color
  • FIG. 17 is a schematic of a light shutter layer having a dye
  • FIG. 18 is a schematic of an interferometric modulator
  • FIG. 19 is a schematic of an array of electronically controlled blinds
  • FIG. 20 is a schematic of an electrophoretic modulator
  • FIG. 21 is a schematic of an electrowetting device
  • FIG. 22 is a schematic of an electrochromic modulator.
  • Optic axis herein refers to the direction in which propagating light does not see birefringence.
  • Polarizer and analyzer herein refer to elements that polarize electromagnetic waves. However, the one closer to the source of the light will be called a polarizer although the one closer to the viewer will be called an analyzer.
  • Polarizing elements herein refers to both the polarizer and analyzer.
  • Azimuthal angle ⁇ and tilt angle ⁇ are herein used to specify the direction of an optic axis. For the transmission axes of the polarizer and the analyzer, only the azimuthal angle ⁇ is used, as their tilt angle ⁇ is zero.
  • FIG. 1 shows the definition of the azimuthal angle ⁇ and tilt angle ⁇ to specify the direction of the optic axis 1 with respect to the x-y-z coordinate system 3.
  • the x-y plane is parallel to the display surface 5, and the z-axis is parallel to the display normal direction 7.
  • the azimuthal angle ⁇ is the angle between the y-axis and the projection of the optic axis 9 onto the x-y plane.
  • the tilt angle ⁇ is the angle between the optic axis 1 and the x-y plane.
  • the invention is enabled by a light source that produces light output which is both nearly collimated and single wavelength.
  • the light source must contain red, green, and blue emitting elements from a common substrate whose size is on the scale of 80 X 240 ⁇ m.
  • a light source that meets these criteria is a two-dimensional vertical cavity surface emitting laser (VCSEL) array device 100, as shown schematically in FIG. 2.
  • FIG. 3 shows a top view of the two-dimensional VCSEL array device 100 where on the surface of the VCSEL needs to be defined red, green, and blue (RGB) emitting elements 205 which are composed of thousands of micron-sized laser pixels 200 separated by interpixel regions 210.
  • RGB red, green, and blue
  • an active region 130 be composed of organic-based gain media.
  • organic-based gain media For example, recent research, R.N. Bhargava, Phys. Stat. Sol. 229, 897 (2002), points to the possibility of obtaining visible wavelength emission from inorganic-based nanoparticles. Examples of these are ZnO nanoparticles (with preferred diameters less than 10 run) either undoped or doped with impurities, such as, Mn 2+ or Eu 2+ .
  • the emission from the various laser pixels 200 needs to be phase-locked, i.e., intensity and phase information must be exchanged amongst the pixels (E. Kapon and M. Orenstein, U.S. Patent 5,086,430).
  • the laser pixels 200 need to be the same size and positioned in a periodic array.
  • having single mode laser output from each emitting element 205 would result in speckle, which is not desirable for display applications.
  • each laser pixel needs to produce single mode output.
  • the preferred diameter of the laser pixels 200 is in the range of 2.5 to 4.5 ⁇ m, where smaller diameters result in increased scattering loss and larger diameters result in unwanted higher-order transverse modes.
  • the generalized methodology for producing a two-dimensional array of laser pixels is to modulate the net gain of the VCSEL device.
  • This modulation of the net gain can be obtained by a number of ways, such as selectively spoiling the emissive properties of the gain media in the active region 130, selectively pumping the gain media in the active region 130, and selectively etching one of the dielectric mirrors (stacks).
  • a straightforward way to spoil the emissive properties of an organic-based gain media is to expose it to high levels of UV radiation.
  • an absorbing layer can be selectively deposited below the active region 130 (in the area underneath the interpixel regions 210) such that it absorbs a pump- beam light 180 prior to it entering the active region 130.
  • the interpixel regions 210 are defined by where the net gain is lowered (through either spoiling the emissive properties or by absorbing the pump-beam light 180), although the two-dimensional array of laser pixels 200 corresponds to the regions where the net gain is unmodified.
  • the modulation is obtained by performing a two-dimensional etch of one of the dielectric stacks, such that, the interpixel regions 210 correspond to the etched areas (lower overall reflectance at the lasing wavelength) of the dielectric stack, whereas the unetched areas (higher overall reflectance at the lasing wavelength) correspond to the laser pixels 200.
  • the light output from VCSEL devices typically does not have a preferred orientation and can vary as a function of light intensity.
  • Ways for fixing the polarization can be broken into two groups: 1) have the oscillator strength of the lasing transition be different for the transverse electric (TE) and transverse magnetic (TM) polarizations; and 2) have the dielectric stack reflectance be different for the two polarizations.
  • the first approach is difficult to implement for gain media comprised of amorphous organic compounds.
  • the reflectance of either the top or bottom dielectric stacks is modified in order to make it birefringent.
  • a 4% difference in the threshold modal gains between the TE and TM polarizations will result in greater than a 100:1 polarization mode suppression ratio (PMSR), Y. Ju, et al., Appl. Phys. Lett. 71, 741 (1997).
  • An effective route to enable this modal difference for amorphous organic laser systems is to replace one of the layers of the dielectric stack (preferably the stack with the lower peak reflectance) with a birefringent layer 126.
  • these birefringent layers can have the index of refraction in the two polarization directions differing by as much as 0.25, with a 0.16 index difference being more common.
  • a standard well known transfer matrix techniques can be used to calculate the modal difference between the two polarizations. The result will be on the order of 22% if one of the stack layers (whose peak reflectance is on the order of 99%) is replaced by the birefringent layer 126, for which the index difference is 0.16. Since this modal difference is far greater than the one measured by Y. Ju, et al., Appl. Phys. Lett. 71 , 741 (1997) for inorganic VCSELs, then the resulting PMSR should be much larger than 100: 1. Even though the VCSEL array device 100 is described with reference to including a birefringent layer 126 in order to polarize the laser light 190, as is well known in the art, Y.
  • the birefringent layer 126 shown in FIG. 2, includes an alignment layer 128 and a birefringent material 129, and is deposited over the bottom dielectric stack 120.
  • the birefringent layer 126 can also be disposed between the active region 130 and a top dielectric stack 140.
  • the birefringent layer 126 can also be disposed within one of the dielectric stacks.
  • the alignment layer 128 can be oriented by the following techniques.
  • the alignment layer contains a photo-orientable or photo- alignable material and can be oriented by a photo-alignment technique.
  • Photo- orientable materials include, for example, photo-isomerization polymers, photo- dimerization polymers, and photo-decomposition polymers.
  • the photo-orientable materials are cinnamic acid derivatives as disclosed in U.S. Patent 6,160,597. Such materials can be oriented and simultaneously crosslinked by irradiation with linearly polarized UV light.
  • the alignment layer can also be oriented by mechanical rubbing, which is well known in the art.
  • the photo-alignment process can be accomplished by using an apparatus as described in commonly assigned U.S. Patent Application Publication 2004/0008310 Al, the disclosure of which is herein incorporated by reference.
  • the optic axis 1 in the birefringent material 129 is usually untilted relative to the layer plane, and is uniform across the thickness direction.
  • the active region 130 is deposited over the bottom dielectric stack 120 or birefi ⁇ ngent layer 126, when it is included in the device.
  • FIG. 2 shows that the active region 130 is not a bulk layer but a multilayer composite.
  • the active region 130 contains one or more periodic gain regions 160, which are separated by spacer layers 170.
  • the thickness of the periodic gain regions 160 is typically less than 50 nm, with a preferred thickness of 5 to 30 nm.
  • the periodic gain region(s) 160 is composed of either small- molecular weight organic material, polymeric organic material, or inorganic-based nanoparticles, which fluoresce with a high quantum efficiency.
  • the small- molecular weight organic material is typically deposited by high- vacuum (10 "6 Torr) thermal evaporation, although the conjugated polymers and inorganic nanoparticles are usually formed by spin casting.
  • the substituent can be, for example, halogen, such as chloro, bromo or fluoro; nitro; hydroxyl; cyano; carboxyl; or groups which can be further substituted, such as alkyl, including straight or branched chain or cyclic alkyl, such as methyl, trifluoromethyl, ethyl, f-butyl, 3-(2,4-di-t-pentylphenoxy) propyl, and tetradecyl; alkenyl, such as ethylene, 2-butene; alkoxy, such as methoxy, ethoxy, propoxy, butoxy, 2-methoxyethoxy, sec-butoxy, hexyloxy, 2-ethylhexyloxy, tetradecyloxy, 2-(2,4-di-t-pentylphenoxy)ethoxy, and 2-dodecyloxyethoxy; aryl such as phenyl, 4-t-butylphenyl
  • the substituents can themselves be further substituted one or more times with the described substituent groups.
  • the particular substituents used can be selected by those skilled in the art to attain the desired properties for a specific application and can include, for example, electron- withdrawing groups, electron-donating groups, and steric groups.
  • the substituents can be joined together to form a ring such as a fused ring unless otherwise provided.
  • the above groups and substituents thereof can include those having up to 48 carbon atoms, typically 1 to 36 carbon atoms and usually less than 24 carbon atoms, but greater numbers are possible depending on the particular substituents selected.
  • Substitution can include fused ring derivatives such as but not limited to benzo-, dibenzo-, naphtha-, or dinaphtho-fused derivatives. These fused ring derivatives can be further substituted as well.
  • An important relationship for choosing a dye as a dopant is a comparison of the absorption of the dopant material and emission of the host material.
  • a necessary condition is that the absorption of the dopant overlaps the emission of the host material.
  • Those skilled in the art are familiar with the concept of Forster energy transfer, which involves a radiationless transfer of energy between the host and dopant molecules.
  • An important relationship for choosing the host material is that the absorption of the host material significantly overlaps the emission spectrum of the pump-beam light 180.
  • it is preferred that the absorption of the host material or a host material plus a dopant is small at the laser emission wavelength of the VCSEL array device 100.
  • An acceptable level of absorption is that the absorption coefficient of the host plus dopant combination is less than 10 cm "1 at the wavelength of the laser emission.
  • Q 1 and Q 2 are independently selected aromatic tertiary amine moieties
  • G is a linking group such as an arylene, cycloalkylene, or alkylene group of a carbon to carbon bond.
  • at least one of Q 1 or Q 2 contains a polycyclic fused ring structure, e.g., a naphthalene.
  • G is an aryl group, it is conveniently a phenylene, biphenylene, or naphthalene moiety.
  • a useful class of triarylamines satisfying structural Formula A and containing two triarylamine moieties is represented by structural Formula B
  • R 1 and R 2 each independently represent a hydrogen atom, an aryl group, or an alkyl group or R 1 and R 2 together represent the atoms completing a cycloalkyl group;
  • R 5 and R 6 are independently selected aryl groups.
  • at least one of R 5 or R 6 contains a polycyclic fused ring structure, e.g., a naphthalene.
  • the host material can comprise a substituted or unsubstituted triarylamine compound.
  • Another class of aromatic tertiary amines is the tetraaryldiamines. Desirable tetraaryldiamines include two diarylamino groups, such as indicated by Formula C, linked through an arylene group. Useful tetraaryldiamines include those represented by Formula D
  • each Are is an independently selected arylene group, such as a phenylene or anthracene moiety; n is an integer of from 1 to 4; and Ar, R 7 , R. 8 , and R 9 are independently selected aryl groups.
  • at least one of Ar, R 7 , R 8 , and R 9 is a polycyclic fused ring structure, e.g., a naphthalene.
  • the various alkyl, alkylene, aryl, and arylene moieties of the foregoing structural Formulae A, B, C, D, can each in turn be substituted.
  • Typical substituents include alkyl groups, alkoxy groups, aryl groups, aryloxy groups, and halogens such as fluoride, chloride, and bromide.
  • the various alkyl and alkylene moieties typically contain from 1 to about 6 carbon atoms.
  • the cycloalkyl moieties can contain from 3 to about 10 carbon atoms, but typically contain five, six, or seven carbon atoms, e.g. cyclopentyl, cyclohexyl, and cycloheptyl ring structures.
  • the aryl and arylene moieties are usually phenyl and phenylene moieties.
  • the emissive material can be formed of a single or a mixture of aromatic tertiary amine compounds. Specifically, one can employ a triarylamine, such as a triarylamine satisfying the Formula B, in combination with a tetraaryldiamine, such as indicated by Formula D.
  • the host material can include a substituted or unsubstiruted dicarbazole-biphenyl compound.
  • useful aromatic tertiary amines is the following:
  • the host material can comprise a substituted or unsubstituted aza- aromatic compound.
  • the host material can comprise a substituted or unsubstituted acridine, quinoline, purine, phenazine, phenoxazine, or phenanthroline compound.
  • Carbazole derivatives are useful hosts.
  • Useful examples of phenanthroline materials include 2,9-dimethyl-4,7-diphenyl-l,10- phenanthroline and 4,7-diphenyl-l,10-phenanthroline.
  • Host and dopant molecules include, but are not limited to, those disclosed in U.S. Patents 4,768,292; 5,141,671; 5,150,006; 5,151,629; 5,405,709; 5,484,922; 5,593,788; 5,645,948; 5,683,823; 5,755,999; 5,928,802; 5,935,720; 5,935,721; and 6,020,078.
  • Form E Metal complexes of 8-hydroxyquinoline and similar derivatives constitute one class of useful host materials capable of supporting electroluminescence, and are particularly suitable for light emission of wavelengths longer than 500 nm, e.g., green, yellow, orange, and red.
  • M represents a metal
  • n is an integer of from 1 to 3;
  • Z independently in each occurrence represents the atoms completing a nucleus having at least two fused aromatic rings.
  • the metal can be monovalent, divalent, trivalent, or tetravalent metal.
  • the metal can, for example, be an alkali metal, such as lithium, sodium, or potassium; an alkaline earth metal, such as magnesium or calcium; an earth metal, such aluminum or gallium, or a transition metal such as zinc or zirconium.
  • alkali metal such as lithium, sodium, or potassium
  • alkaline earth metal such as magnesium or calcium
  • earth metal such aluminum or gallium, or a transition metal such as zinc or zirconium.
  • any monovalent, divalent, trivalent, or tetravalent metal known to be a useful chelating metal can be employed.
  • Z completes a heterocyclic nucleus containing at least two fused aromatic rings, at least one of which is an azole or azine ring. Additional rings, including both aliphatic and aromatic rings, can be fused with the two required rings, if required. To avoid adding molecular bulk without improving on function the number of ring atoms is usually maintained at 18 or less.
  • the host material can comprise a substituted or unsubstituted chelated oxinoid compound.
  • CO-I Aluminum trisoxine [alias, tris(8-quinolmolato)aluminum(III)]
  • CO-2 Magnesium bisoxine [alias, bis(8-quinolinolato)magnesium(II)]
  • CO-3 Bis[benzo ⁇ f ⁇ -8-quinolinolato]zinc (II)
  • CO-4 Bis(2-methyl-8-quinolinolato)aluminum(III)- ⁇ -oxo-bis(2-methyl-8- quinolinolato) aluminum(III);
  • CO-5 Indium trisoxine [alias, tiis(8-quinolinolato)indium]
  • CO-6 Aluminum tris(5-methyloxine) [alias, tris(5-methyl-8-quinolinolato) aluminum(III)];
  • CO-7 Lithium oxine [alias, (8-quinolinolato)lithium(I)]; CO-8: Gallium oxine [alias, tris(8-quinolinolato)gallium(III)]; and CO-9: Zirconium oxine [alias, tetra(8-quinolinolato)zirconium(IV)].
  • the host material can include a substituted or unsubstituted anthracene compound.
  • Form F Derivatives of 9,10-di-(2-naphthyl)anthracene (Formula F) constitute one class of useful hosts capable of supporting photoluminescence, and are particularly suitable for light emission of wavelengths longer than 400 nm, e.g. blue, green, yellow, orange or red.
  • R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 represent one or more substituents on each ring where each substituent is individually selected from the following groups:
  • Group 1 hydrogen, or alkyl of from 1 to 24 carbon atoms
  • Group 2 aryl or substituted aryl of from 5 to 20 carbon atoms;
  • Group 3 carbon atoms from 4 to 24 necessary to complete a fused aromatic ring of anthracenyl, pyrenyl, or perylenyl;
  • Group 4 heteroaryl or substituted heteroaryl of from 5 to 24 carbon atoms as necessary to complete a fused heteroaromatic ring of furyl, thienyl, pyridyl, quinolinyl or other heterocyclic systems;
  • Group 5 alkoxylamino, alkylamino, or arylamino of from 1 to 24 carbon atoms;
  • Group 6 fluorine, chlorine, bromine or cyano.
  • Illustrative examples include 9,10-di-(2-naphthyl)anthracene (Fl) and 2-t-butyl-9,10-di-(2-naphthyl)anthracene (F2).
  • Other anthracene derivatives can be useful as a host, including derivatives of 9,10-bis-(4-(2,2'- diphenylethenyl)phenyl)anthracene.
  • Benzazole derivatives constitute another class of useful hosts capable of supporting photoluminescence, and are particularly suitable for light emission of wavelengths longer than 400 nm, e.g., blue, green, yellow, orange or red.
  • n is an integer of 3 to 8.
  • Z is O, NR or S
  • R and R are individually hydrogen; alkyl of from 1 to 24 carbon atoms, for example, propyl, t-butyl, heptyl, and the like; aryl or hetero-atom substituted aryl of from 5 to 20 carbon atoms for example phenyl and naphthyl, furyl, thienyl, pyridyl, quinolinyl and other heterocyclic systems; or halo such as chloro, fluoro; or atoms necessary to complete a fused aromatic ring; and
  • L is a linkage unit including alkyl, aryl, substituted alkyl, or substituted aryl, which conjugately or unconjugately connects the multiple benzazoles together.
  • An example of a useful benzazole is 2, 2', 2"-(l,3,5- phenylene)tris[ 1 -phenyl- 1 H-benzimidazole] .
  • the host material can comprise a substituted or unsubstituted benzoxazole compound, a substituted or unsubstituted benzothiazole compound, or a substituted or unsubstituted benzimidazole compound.
  • the host material can comprise a substituted or unsubstituted oxazole compound, a substituted or unsubstituted triazole compound, or a substituted or unsubstituted oxadiazole compound.
  • oxazole compounds include l,4-bis(5- ⁇ henyloxazol-2-yl)benzene, 1 ,4-bis(4-methyl-5-phenyloxazol-2-yl)benzene, and l,4-bis(5-(p-biphenyl)oxazol-2-yl)benzene.
  • oxadiazole compounds include 2-(4-biphenylyl)-5-phenyl-l,3,4-oxadiazole and 2-(4- biphenylyl)-5-(4-tert-butylphenyi)-l,3,4-oxadiazole.
  • triazole compounds include 3-(4-biphenylyl)-4-phenyl-5-tert-butylphenyl-l ,2,4-triazole.
  • Distyrylarylene derivatives are also useful as host materials or dopant materials. Many examples are described in U.S. Patent 5,121,029. Useful emissive materials (hosts and dopants) can have the general Formulae
  • X and Z are independently a substituted or unsubstituted aromatic group or a substituted or unsubstituted aromatic complex ring group having one nitrogen atom; n equals 1, 2, or 3; and
  • Y is a divalent aromatic group or a divalent aromatic complex ring group having one nitrogen atom.
  • Useful examples mcludel,4-bis(2-methylstyryl)- benzene, 4,4'-(9, 10-anthracenediyldi-2, 1 -ethenediyl)bis(N,N-bis(4-methylphenyl)- benzenamine, 4,4'-(l ,4-na ⁇ hthalenediyldi-2, 1 -ethenediyl)bis(N,N-bis(4- methylphenyl)benzenamine, and 4,4'-(l,4-phenylenedi-2,l-ethenediyl)bis(N,N-(4- tolyl))benzeneamine.
  • the organic-based dopant is selected to provide emission between 300-1700 nm.
  • the dopant can be selected from fluorescent or phosphorescent dyes.
  • Useful fluorescent dopants include materials as described as host materials above. Other useful fluorescent dopants include, but are not limited to, derivatives of substituted or unsubstituted anthracene, tetracene, xanthene, perylene, rubrene, coumarin, rhodamine, and quinacridone, dicyanomethylenepyran compounds, thiopyran compounds, polymethine compounds, pyrilium and thiapyrilium compounds, fluorene derivatives, periflanthene derivatives, indenoperylene derivatives, bis(azinyl)amine boron compounds, bis(azinyl)methane compounds, napthyridine, fluoranthene, furan, indole, thiaphene, benzoxanthene, pyrene, peropyrene
  • useful dopants include, but are not limited to, the following:
  • the emissive material can also be a polymeric material, a blend of two or more polymeric materials, or a doped polymer or polymer blend.
  • the emissive material can also include more than one nonpolymeric and polymeric material with or without dopants. Typical dopants are listed previously for nonpolymeric molecules. Nonpolymeric dopants can be molecularly dispersed into the polymeric host, or the dopant could be added by copolymerizing a minor constituent into the host polymer.
  • Typical polymeric materials include, but are not limited to, substituted and unsubstituted poly(p-phenylenevinylene) (PPV) derivatives, substituted and unsubstituted poly(p-phenylene) (PPP) derivatives, substituted and unsubstituted polyfluorene (PF) derivatives, substituted and unsubstituted poly(p-pyridine), substituted and unsubstituted poly(p- pyridalvinylene) derivatives, and substituted, unsubstituted poly(p-phenylene) ladder and step-ladder polymers, and copolymers thereof as taught by Diaz-Garcia, et al. in U.S. Patent 5,881,083 and references therein.
  • the substituents include but are not limited to alkyls, cycloalkyls, alkenyls, aryls, heteroaryls, alkoxy, aryloxys, amino, nitro, thio, halo, hydroxy, and cyano.
  • Typical polymers are poly(p- phenylene vinylene), dialkyl-, diaryl-, diamino-, or dialkoxy-substituted PPV, mono alkyl-mono alkoxy-substituted PPV, mono aryl-substituted PPV, 9,9'- dialkyl or diaryl-substituted PF, 9,9'-mono alky-mono aryl substituted PF, 9-mono alky or aryl substituted PF, PPP, dialkyl-, diamino-, diaryl-, or dialkoxy- substituted PPP, mono alkyl-, aryl-, alkoxy-, or amino-substituted PPP.
  • polymeric materials can be used such as poly(N-vinylcarbazole) (PVK), polythiophenes, polypyrrole, polyaniline, and copolymers such as poly(3,4- ethylenedioxythiophene)/poly(4-styrenesulfonate) also called PEDOT/PSS.
  • PVK poly(N-vinylcarbazole)
  • polythiophenes polypyrrole
  • polyaniline polyaniline
  • copolymers such as poly(3,4- ethylenedioxythiophene)/poly(4-styrenesulfonate) also called PEDOT/PSS.
  • the organic materials mentioned above are suitably deposited through sublimation, but can be deposited from a solvent with an optional binder to improve film formation. If the material is a polymer, solvent deposition is usually preferred.
  • the material to be deposited by sublimation can be vaporized from a sublimator "boat" often comprised of a tantalum material, e.g. as described in U.S. Patent 6,237,529, or can be first coated onto a donor sheet and then sublimed in closer proximity to the substrate. Layers with a mixture of materials can utilize separate sublimator boats or the materials can be pre-mixed and coated from a single boat or donor sheet.
  • the spacer layer 170 it is preferred to use a material that is highly transparent to both the laser light 190 and the pump-beam light 180.
  • 1 -Bis-(4-bis(4-methyl-phenyl)-amino-phenyl)-cyclohexane (TAPC) is chosen as the spacer material, since it has very low absorption throughout the visible and near UV spectrum and its index of refraction is slightly lower than that of most organic host materials. This refractive index difference is useful since it helps in maximizing the overlap between the standing e-field antinodes and the periodic gain region(s) 160.
  • the lower net gain regions 150 are produced by locally spoiling the emissive properties of the periodic gain region(s) 160.
  • An effective way to form the lower net gain regions 150 is to use standard photolithographic masks and UV exposing apparatus in order to produce a patterned UV exposure of the periodic gain region(s) 160. Since organic media is sensitive to high intensity UV light (for example the mercury arc lamp's i-line at 365 nm), this technique works very effectively to lower the emissive intensity of the UV exposed areas of the periodic gain region(s) 160.
  • the UV exposed areas correspond to the interpixel region 210, although the unexposed areas correspond to the laser pixels 200.
  • the shape of the laser pixels 200 is circular; however, other pixel shapes are possible, such as rectangular.
  • the size of the laser pixels 200 is in the range of 2.5 to 20 microns.
  • the preferred laser pixel 200 diameter is 2.5 to 4.5 ⁇ m.
  • the interpixel spacing is in the range of 0.25 to 4 ⁇ m.
  • the spaced laser pixels 200 can have the same or different sizes and the spacing between pixels can have the same or different lengths to cause the output of the VCSEL array device 100 to produce locally single or multimode laser output.
  • the emissive intensity of the periodic gain region(s) 160 can be locally modulated by ways other than high intensity UV radiation, such as those ways commonly practiced in the art.
  • the top dielectric stack 140 is spaced from the bottom dielectric stack 120 and reflective to light over a predetermined range of wavelengths. Its composition is analogous to that of the bottom dielectric stack. Since the top dielectric stack 140 is deposited over an active region 130 that contains organics (for the case of organic-based gain media), its deposition temperature must be kept low in order to avoid melting the organics. As a result, a typical deposition temperature for the top dielectric stack 140 is 100°C or lower.
  • the top dielectric stack can be deposited by conventional ways, such as e-beam, low-energy sputtering, or colloidal deposition. In order to obtain effective lasing performance, it is preferred that the peak reflectivities of the top and bottom dielectric stacks be greater than 99%, where smaller values result in larger lasing linewidths.
  • the VCSEL array device 100 is optically driven by an incident pump-beam light 180 and emits laser light 190.
  • the pump-beam can be incoherent LED light.
  • FIG. 2 shows laser light 190 through the top dielectric stack 140.
  • the laser structure could be optically pumped through the top dielectric stack 140 with the laser light 190 through the substrate 110 by proper design of the dielectric stack reflectance properties.
  • the operation of the VCSEL array device 100 occurs by the following ways.
  • the pump-beam light 180 transmits through the substrate 110 and the bottom dielectric stack 120 and is absorbed by the periodic gain region(s) 160, wherein some fraction of the pump-beam energy is re-emitted as longer wavelength laser light at the position of the laser pixels 200.
  • the pump-beam light 180 enters through the substrate 110, to ensure that the laser light 190 mainly exits through the top dielectric stack 140, it is necessary to choose the top dielectric stack peak reflectance to be smaller than the bottom dielectric stack 120 peak reflectance.
  • the top dielectric stack 140 is highly reflective to the pump-beam light 180 and the bottom dielectric stack 120 is highly transmissive to the pump-beam light 180.
  • FIG. 4 Another embodiment of the present invention is given in FIG. 4, laser array device 102, which contains absorbing elements 155.
  • the absorbing elements 155 be placed adjacent to the active region 130.
  • performing photolithographic-based processing on laser devices is difficult once the organics have been deposited; accordingly, it is preferred to place the absorbing elements between the birefringent layer 126 and the active region 130 as shown in FIG. 4.
  • the composition of the absorbing elements 155 is any material that absorbs the pump-beam light 180 and only minimally absorbs and scatters the laser light 190. It is preferred that at the emission wavelengths of the pump-beam light 180, the absorbing elements' 155 absorption coefficient is greater than 10 cm "1 .
  • the thickness of the absorbing elements 155 is chosen such that a significant percentage of the pump-beam light 180 is absorbed by the elements. A preferred absorption fraction is greater than 25%. With regard to producing a patterned absorber layer, this can be accomplished by a number of ways. The first way is to deposit a uniform dye layer 157 and use patterned UV light to modify selectively the absorption coefficient of the dye layer 157. As discussed above with reference to FIG.
  • the UV light can be patterned using conventional photolithographic masks.
  • this can be accomplished either through bleaching the dye molecules (lowering the absorption selectively) or by dissociating the dye molecules to produce a species, which more strongly absorbs the pump-beam light 180 (raising the absorption selectively).
  • both the dye layer 157 and the absorbing elements 155 only weakly absorb/scatter the laser light 190.
  • a nice feature of this way of producing the absorbing elements 155 is that it results in laser array device 102 being planar.
  • Another way for depositing the absorbing elements 155 is to use a dyed photoresist.
  • the resulting laser array device 103 is illustrated in FIG. 5.
  • These types of dyed photoresists are well known in the art, and are spin cast and patterned by standard photolithographic techniques.
  • the active region 130 and the top dielectric stack 140 are deposited in sequence. Since the absorbing elements 155 need to be placed between the birefringent layer 126 and the active region 130, and absorb a portion of the pump-beam light 180, it is necessary for the pump-beam light 180 to enter through the substrate 110.
  • etched pits can be formed in a transparent layer (such as SiO 2 ), over which can be deposited the absorbing elements 155 material.
  • CMP chemical mechanical polishing
  • the positions of the absorbing elements 155 correspond to the interpixel region 210, although the remaining areas correspond to the laser pixels 200.
  • the shape of the laser pixels 200 is circular; however, other pixel shapes are possible, such as rectangular.
  • the size of the laser pixels 200 is in the range of 2.5 to 20 microns.
  • the preferred laser pixel 200 diameter is 2.5 to 4.5 Dm.
  • the interpixel spacing is in the range of 0.25 to 4 Dm.
  • the spaced laser pixels 200 can have the same or different sizes and the spacing between pixels can have the same or different lengths to cause the output of the laser array device 102 or 103 to produce locally single or multimode laser output.
  • FIG. 6 shows another embodiment of the present invention.
  • This laser array device 104 is a variation of the one illustrated in FIG. 5. In FIG. 5 the active region 130 is grown directly on the absorbing elements 155.
  • the active region 130 and the top dielectric stack 140 are deposited on a non-planar (corrugated) surface for the case of the absorbing elements formed by dyed photoresist (note that the case of growing in the etch pits followed by CMP results in a planar surface).
  • the absorbing elements 155 are planarized by a planarization layer 158, using techniques well known in the art, prior to depositing the active region 130.
  • the planarization layer 158 material is deposited by suitable processes. Next, using CMP techniques, which are well known in the art, the planarization layer 158 material is polished until it is flush (or within a couple tens of nanometers) with the top surface of the absorbing elements 155.
  • a second embodiment of the planarization layer 158 is to use polymethylmethacrylate (PMMA). hi this case PMMA is spun cast over the spaced apart absorbing elements 155 to a thickness range of .5 to 3.0 Dm, followed by a conventional bake at 150 to 22O 0 C.
  • PMMA polymethylmethacrylate
  • FIG. 7 shows another embodiment of the present invention, laser array device 106.
  • the way for spatially modulating the net gain of the VCSEL device is to etch selectively (reflectance modulation) the bottom dielectric stack 120.
  • the etched surface of the bottom dielectric stack be removed from the position of the active region 130 where the intensity of the standing electromagnetic field (e-field) is highest.
  • the bottom dielectric stack 120 is deposited in two parts, a first portion 121 and a second portion 125, whereby the reflectance modulation is obtained by forming an etched region 151 in the surface of the first portion of the bottom dielectric stack 121.
  • the first portion of the bottom dielectric stack 121 contain at most 3 to 5 dielectric layers which reflect the laser light. For cases where additional dielectric layers are added to the bottom stack for reflecting the pump-beam light 180 back into the active region 130, these layers are to be deposited first in the first portion of the bottom dielectric stack 121.
  • the patterned etched region 151 is formed in the first portion of the bottom dielectric stack 121 by using standard photolithographic and etching techniques, thus forming a two-dimensional array of circular pillars on the surface of the first portion of the bottom dielectric stack 121.
  • the shape of the laser pixels is circular; however, other pixel shapes are possible, such as rectangular.
  • the interpixel spacing is in the range of 0.25 to 4 ⁇ m.
  • the second portion of the bottom dielectric stack 125 is deposited over the first portion of the bottom dielectric stack 121 after having formed the etched region 151. As shown schematically in FIG. 7, the second portion of the bottom dielectric stack 125 fills the etched region 151.
  • the second portion of the bottom dielectric stack 125 is composed of alternating layers of high and low refractive index dielectric materials, such as TiO 2 and SiO 2 , respectively.
  • the first portion the second portion can be deposited by e-beam, PECVD, sputtering, sol-gel methods or colloidal deposition.
  • FIG. 8 shows another embodiment of the present invention, laser array device 108. This device is a variation of the one illustrated in FIG. 7. In FIG.
  • the second portion of the bottom dielectric stack 125 is grown directly on the etched region 151.
  • the stack is deposited on a non-planar (corrugated) surface.
  • deposition on a corrugated surface can lead to columnar growth of the stacks.
  • the etched surface of the first portion of the bottom dielectric stack 121 is planarized by a planarization layer 158 prior to depositing the second portion of the bottom dielectric stack 125.
  • planarization layer 158 is polyimide for the Ta 2 O 5 -SiO 2 or TiO 2 -SiO 2 multilayer stack systems. Following the production of the etched regions 151, 2 to 3 microns of polyimide are deposited on the surface of the first portion of the bottom dielectric stack 121 by spin casting and then hardened by a bake at temperatures ranging from 180 to 250°C. Next, using CMP techniques, which are well known in the art, the polyimide is polished until it is flush (or within a couple tens of nanometers) with the top surface of the first portion of the bottom dielectric stack 121 at the positions of the laser pixels 200. Because of the large difference in the polish rates of polyimide and oxides in standard CMP slurries, it is straightforward to have the polishing stop just as it begins to polish the oxide layers at the positions of the laser pixels 200.
  • the planarization layer 158 of SiO 2 is deposited at a thickness of 0.75 to 2.0 ⁇ m by either CVD or thermal evaporation.
  • CMP is used with another common slurry to polish the SiO 2 until it is flush (or within a couple tens of nanometers) with the top of the silicon nitride layer.
  • a polish selectivity of greater than 3.5:1 it is again straightforward to stop the polishing as it begins to polish the top of the silicon nitride layer.
  • a third embodiment of the planarization layer 158 is PMMA for any multilayer dielectric stack system.
  • PMMA is spun cast over the etched surface of the first portion of the bottom dielectric stack 121 to a thickness range of .5 to 3.0 ⁇ m, followed by a conventional bake at 150 to 220°C.
  • a conventional bake at 150 to 220°C is possible as practiced by those skilled in the art.
  • the addition of the planarization layer 158 following the production of the etched regions 151 and prior to the deposition of the second portion of the bottom dielectric stack 125 leads to less scattering loss in the active region 130 and in the bottom and top dielectric stacks and results in higher power conversion efficiencies.
  • a liquid crystal display can be made.
  • the more simplified LCD typically contains a backlight unit 220, the VCSEL array device 100, a polarizer layer 305, a light shutter layer 310, and a beam expander 320.
  • the backlight unit 220 provides the pump-beam light 180 for the VCSEL array device 100.
  • the VCSEL array device 100 provides a colored, pixelated light source for the light shutter layer 310. If the VCSEL array ' device 100 includes the birefringent layer 126, then its output is also polarized and the polarizer layer 305 can be limited.
  • the polarizer layer 305 passes one polarization of the laser light 190 to the light shutter layer 310.
  • the light shutter layer 310 either passes or blocks polarized light in a pixelated structure.
  • the beam expander 320 takes the light exiting the light shutter layer 310 and expands its viewing cone.
  • the backlight unit 220 is comprised of a diffuser 240 and either light emitting diodes (LEDs) 230 or a cold cathode fluorescent lamp (CCFL) 280.
  • the diffuser 240 homogenizes the light incident on the VCSEL array device 100.
  • the LEDs 230 are typically either in a linear array 250 illuminating the edge of a waveguide 260, which then redirects the light such that it is illuminating the VCSEL array device 100, or in a planar array 270 directly illuminating the VCSEL array device 100.
  • the CCFL 280 is typically either illuminating the edge of the waveguide 260, which redirects the light such that it is illuminating the VCSEL array device 100, or oriented in rows 300 underneath the difruser and directly illuminating the VCSEL array device 100.
  • the small divergence angle of the VCSEL array device 100 enables a 1 :1 correspondence between the laser array's emitting elements 205 and the light shutter layer's 310 color elements.
  • the light shutter layer 310 only needs to modulate the colored light incident from the VCSEL array device 100; thus, limiting the efficiency loss associated with color filter arrays.
  • An additional feature of the near collimation of the light output from the VCSEL array device 100 is that the viewing angle compensation films can be removed from the display structure.
  • the collimating films which are typically included in the backlight unit 220, can be removed.
  • the cost of the liquid crystal display device can be reduced.
  • the very small divergence of the VCSEL array device 100 light output must be accounted for.
  • the size of the laser array's emitting elements 205 must be slightly reduced in order that the laser light upon traversing into the light shutter layer 310 will subtend the proper pixel dimension of approximately 80 x 240 ⁇ m.
  • the size of the emitting elements can be adjusted by selectively depositing metal between the bottom dielectric stack 120 and the substrate 110.
  • Preferred metals are Al or Ag which can be selectively deposited by well known evaporation techniques. These metals are highly reflective of the pump-beam light 180 and will cause the recycling of the pump-beam light 180 until it passes between the metal depositions.
  • the multimode laser light output from the two-dimensional vertical cavity laser array will be polarized preferentially along one direction.
  • the bottom polarizer element and its associated reflective polarizer element are not needed in the backlight unit 220. Removal of these elements from the display structure results in a cost savings.
  • no effort can be made to preferentially polarize the VCSEL output. In that case it will be necessary to add the polarizer layer 305 in between the top of the VCSEL array device 100 and the bottom of the light shutter layer 310.
  • the added polarizer layer 305 be as thin as practical. For example, recent polarizers have thicknesses on the order of lO ⁇ m.
  • the light shutter layer 310 is typically a liquid crystal cell 330 with an analyzer 340 on the side farthest from the VCSEL array device 100.
  • the liquid crystal cell 330 is analogous to conventional liquid crystal cells except that it does not contain a CFA.
  • the liquid crystal cell 330 does not require a CFA since the light output from the VCSEL array device 100 is pixelated into red, green, and blue laser light emission.
  • the liquid crystal cell 330 comprises liquid crystal substrates 350 on the top and bottom.
  • the liquid crystal substrates 350 in the liquid crystal cell 330 can include either glass plates or plastic substrates.
  • the thickness of the liquid crystal substrates 350 should be sufficiently thin to prevent parallax, which would result in light leakage through adjacent pixels.
  • the thickness of the liquid crystal substrates 350 should preferably be less then 0.5 mm. Both of the liquid crystal substrates 350 are coated with a patterned transparent conductor layer 360. Typical transparent conductors are indium tin oxide. On top of each of the transparent conductor layers 360 is coated an alignment layer 370. Lastly, between the two alignment layers 370 is coated the liquid crystal material 380.
  • the liquid crystal cell 330 modulates the light intensity output from the VCSEL array device 100 by orienting the liquid crystal molecules upon selective application of voltages.
  • the liquid crystal cell 330 can also contain thin film transistors at each pixel location, permitting the display to be driven actively. However, the invention does not require a specific drive scheme.
  • the light shutter layer 310 also contains the analyzer 340 which resolves the polarized light output from the liquid crystal cell 330.
  • FIG. 1 An example is a light shutter produced by electro wetting.
  • this light switch as demonstrated by Hayes, et al., Nature, 425, 383 (2003), the application of an electric field changes the degree to which dye- containing oil droplets cover the surface of each pixel. In effect, the electric field modifies the hydrophobicity of the pixel surface.
  • Hayes, et al., Nature, 425, 383 (2003) envisioned their switch used for a reflective display, where the reflection is produced by a white reflector in back of the oil droplets.
  • the electrowetting switch could also be used in transmission if the backplane is clear instead of reflective.
  • a beam expander 320 As the final element of the LCD device of FIG. 9 in order to increase the angular cone of the colored light output.
  • Possible components comprising the beam expander 320 can be a diffuser element or a microlens array. The component should be such that it increases the viewing cone although preserving the sharpness of the display image. More specifically, upon exiting the beam expander 320, each pixel should be as clearly distinguishable as prior to entering the beam expander 320. Depending on the intended application, the expansion of the viewing cone by the beam expander 320 can be adjusted accordingly.
  • Light shutter layer 310 modulates light emitted from VCSEL array device 100 in order to form an image.
  • light shutter layer 310 acts as a type of spatial light modulator for illumination emitted by VCSEL array device 100.
  • the display apparatus of the present invention admits a number of types of components and technologies for this purpose, including diverse types of spatial light modulators. These various types of light modulators can modulate the emitted light using any of a number of mechanisms, including, but not limited to:
  • Light shutter layer 310 is transmissive in the embodiments shown. Since VCSEL array device 100 emits pixelated light of primary color wavelengths (typically red, green, and blue or RGB), there is no need for color filters as part of light shutter layer 310 or in the path of illumination or modulated light.
  • primary color wavelengths typically red, green, and blue or RGB
  • LC cell 330 modulates incident illumination by changing its polarization state.
  • the analyzer 340 is present; therefore, the VCSEL array device 100 must emit polarized light.
  • the bottom polarizer 305 can be omitted, as in FIG. 14.
  • both a polarizer 305 and analyzer 340 are included.
  • the light shutter layer 310 is a liquid crystal (LC) cell 330 having a liquid crystal layer 380 with one or more alignment layers 370, sandwiched between transparent electrode layers 360 having a patterned conductor using indium tin oxide (ITO) or other suitable material.
  • ITO indium tin oxide
  • LC cell 330 can be a passive matrix type, using external drive components for each matrix row; alternately, LC cell 330 can be an active matrix type, wherein a thin-film transistor (TFT) is fabricated as part of the pixel structure itself.
  • TFT thin-film transistor
  • These components of LC cell 330 are encased within transparent substrates 350, typically of glass or plastic where the substrate closer to the VCSEL is sufficiently thin to minimize parallax, preferably thinner than 0.5mm.
  • Front and rear polarizers 340 and 305 are provided on each side of liquid crystal cell 330. The rear polarizers can also be referred to as the analyzer.
  • VCSEL array device 100 Because VCSEL array device 100 emits colored light that is already pixelated into primary colors of visible red, green, and blue wavelengths, no color filter array (CFA) is necessary, as would be commonly used when employing a liquid crystal device having a conventional broadband illumination source. If the VCSEL array device 100 emits polarized light, then the bottom polarizer 305 can be omitted, as in FIG. 14.
  • CFA color filter array
  • LC cell 330 in the configuration of FIG. 15 modulates light emitted from VCSEL array device 100 by orienting LC molecules in response to an applied voltage level.
  • This type of LC cell 330 requires polarized light incident on the LC cell 330 either by a polarized output from VCSEL array device 100 or a polarizer 305.
  • LC cells 330 of this class can be any of a number of commercially available devices that are suitable for transmissive applications, including but not limited to these types: Twisted Nematic (TN); Super Twisted Nematic (STN); Ferroelectric; Zenithal Bistable Device (ZBD), Vertically Aligned (VA) types including Multidomain Vertically Aligned (MVA), PVA; In-Plane Switching (IPS); and Electrically Controlled Birefringence (ECB) types.
  • TN Twisted Nematic
  • STN Super Twisted Nematic
  • ZBD Zenithal Bistable Device
  • VA Vertically Aligned
  • MVA Multidomain Vertically Aligned
  • PVA Multidomain Vertically Aligned
  • IPS In-Plane Switching
  • EBC Electrically Controlled Birefringence
  • FIGS. 14 and 15 represent a substantial number of LC device types, not all liquid crystal devices modulate light in the same manner. There are also varieties of liquid crystal devices that employ different light modulation mechanisms. When used as part of shutter layer 310, these different devices would use different configurations of supporting optical layers. Advantageously, these alternate types of LC modulation do not require supporting polarizers. Thus, brightness losses can be reduced.
  • LC device modulates light using interference effects.
  • FIG. 16 there is shown a configuration of light shutter layer 310 using a cholesteric liquid crystal (ChLC) layer 410.
  • ChLC cholesteric liquid crystal
  • the LC molecules have a helical rotation configuration, with periodicity on the order of the wavelength of the incident light. Using constructive interference, each pixel can be switched between a transparent state and a reflective state for a specific range of wavelengths.
  • the cholesteric LCs only need to reflect light in a narrow wavelength range.
  • the red emitting pixel needs to be placed a red reflecting cholesteric LC.
  • the three colors can be stacked on top of each other as shown in FIG. 15.
  • the red, green, and blue reflecting LCs are labeled 42Or, 42Og, and 420b, respectively.
  • red LC in the light state the red LC is transmitting red light, although the green and blue LCs should be in the states which allow maximum red light transmission; in the dark state, the red LC would reflect red light, although the states of the green and blue LCs remain the same.
  • cholesteric liquid crystal layer 410 has one or more alignment layers, sandwiched between transparent electrode layers having a patterned conductor using indium tin oxide (ITO) or other suitable material.
  • ITO indium tin oxide
  • Components of the cholesteric liquid crystal layer 410 are encased within transparent substrates 440, typically of glass or plastic where the substrate closest to the VCSEL is sufficiently thin to minimize parallax, preferably thinner than 0.5mm.
  • transparent substrates 440 typically of glass or plastic where the substrate closest to the VCSEL is sufficiently thin to minimize parallax, preferably thinner than 0.5mm.
  • Another class of LC device that does not require supporting polarizers includes the smectic-A and guest host liquid crystal types. These types of LC devices utilize absorptive dyes that are aligned with orientable LC molecules, and switch between color and clear states.
  • an LC employing a red absorbing dye can be placed above the red pixel, or a stacked configuration can be used.
  • the LC layer containing red absorbing dye needs to have the dye molecules aligned so that very little red light is absorbed (allowing maximum red light transmission).
  • a black dye could be used with smectic-A or guest host LC types as is shown in FIG. 17 for light shutter layer 310.
  • an LC cell 430 has a liquid crystal layer 480 having one or more alignment layers 470, sandwiched between transparent electrode layers 460 having a patterned conductor using indium tin oxide (ITO) or other suitable material.
  • ITO indium tin oxide
  • LC cell 430 can be a passive matrix type, using external drive components for each matrix row; alternately, LC cell 430 can be an active matrix type, wherein a thin- film transistor (TFT) is fabricated as part of the pixel structure itself.
  • TFT thin- film transistor
  • LC cell 430 These components of LC cell 430 are encased within transparent substrates 440, typically of glass or plastic, where the substrate closer to the VCSEL is sufficiently thin to minimize parallax, preferably thinner than 0.5 mm. Because VCSEL array device 100 emits colored light that is already pixelated into primary colors red, green, and blue wavelengths, no color filter array (CFA) is necessary. Polarizers would not be needed.
  • transparent substrates 440 typically of glass or plastic
  • FIG. 18 shows light shutter array 310 in an embodiment using an interferometric modulator 480.
  • a first thin film stack 482 is created on a transparent substrate 484.
  • a movable membrane 486 is used to vary the distance between the first thin film stack 482 and a second thin film stack 488.
  • Another alternate type of spatial light modulator that can be used as light shutter 310 is a movable micromechanical structure that is actuated to wholly or partially obstructs the light path, blocking or absorbing light.
  • a micromechanical structure would be advantageous for its applicability to light of any wavelength.
  • One type of proposed spatial light modulator employs an array of electronically controlled blinds.
  • FIG. 19 there is shown, in a side view, a single roll blind 490 that could be controlled to wholly or partially block light emitted for a pixel 500.
  • roll blind 490 Consisting of a film element of some type, roll blind 490 can be electrostatically attracted or repelled in order to unroll, absorbing- some portion of light for pixel 500, or to roll up, leaving a clear aperture for light for pixel 500. Since the unrolled roll blind absorbs visible light of all wavelengths, only one roll blind switch is required for all of the emitting pixels. Using Absorptive Particulate Materials
  • Another alternate type of spatial light modulator that can be used as light shutter 310 uses light absorptive particles.
  • Application of an electric field to an electrophoretic cell positions the particles accordingly, which either causes the particles to absorb incident light for the pixel or causes them to move to either side of the cell, thus allowing light transmission through the cell.
  • electrophoretic modulators have been developed for reflective applications, such as for flexible "electronic paper" displays for example.
  • transmissive adaptations of this technology, using appropriately positioned electrodes and particles with the appropriate absorption characteristics, offers some promise for light modulation with VCSEL sources.
  • So-called "liquid powder” devices such as those being developed by Bridgestone, provide another type of spatial light modulator that can be used similarly to electrophoretic devices for shutter 310.
  • This technology utilizes absorptive particles in air or some other gas, the particles being positioned within a pixel cell based on an applied electric field.
  • transmissive versions of these devices would require the use of absorptive particles which can be deflected to the sides of the cells using appropriately positioned electrodes.
  • absorptive liquid In electro wetting technology, a light- absorptive liquid is sandwiched in a cell between a hydrophobic insulator and an immiscible, but transparent liquid, such as water. With no field applied, the light absorptive liquid maximizes its interface between the water and the insulator by laying flat. Application of an electric field changes the energetics of the system such that the light absorptive media beads up.
  • the insulator sits above a reflective substrate; since the substrate needs to be transmissive to the pixel light. As such, the off state occurs with no field applied, although the on state (light transmission) occurs with the field applied.
  • the absorptive media can be either black or could contain red, green, or blue dyes (corresponding to the red, green, or blue emitting pixels).
  • electrochromic modulator Yet another alternate type of spatial light modulator that can be used as a light shutter 310 is an electrochromic modulator.
  • oxidation state dependent molecular absorption is the mechanism whereby variable coloration is achieved.
  • a transmissive device the electrochromic modulator employs an ion-permeable material as the cathode, such as, transition metal oxides or viologens, whereby upon application of a field, electrons and charge compensating ions are injected into the cathode.
  • the material changes its absorption characteristics.
  • the material is transparent in the off-field state, and absorptive in the charge-injected state.
  • electrochromic spatial light modulators act as variable color filters. Since the organic VCSEL device's 100 pixels are colored, one embodiment is to use, for example, a red absorbing electrochromic material above the red pixel. If the electrochromic material becomes dark (for the red, green, and blue pixels) upon application of the field, then the electrochromic switch can be limited to a single material for all three pixel types.
  • FIG. 22 shows a configuration of shutter 310 having an array of cells 570 using a spatial light modulator 550 such as an electrochromic modulation utilizing an ion-permeable material such as the cathode 620 to shift molecular absorption of light.

Abstract

L'invention concerne un appareil permettant de former une image colorée sur un dispositif d'affichage. Cet appareil comprend un dispositif de réseau VCSEL (100) possédant plusieurs pixels émettant de la lumière, chaque pixel émettant de la lumière produisant un faisceau de lumière comprenant des composantes substantielles dans une partie du spectre visible de façon que des pixels émettant de la lumière différents produisent une lumière colorée différente. L'invention concerne également une couche d'obturateur de lumière (310) pour chaque pixel émettant de la lumière, cette couche constituant un modulateur placé dans le trajet du faisceau de lumière correspondant pour faire passer de façon sélective la lumière colorée correspondante afin d'obtenir une image de lumière colorée sur le dispositif d'affichage.
PCT/US2006/030832 2005-08-23 2006-08-08 Formation d'image couleur sur un dispositif d'affichage WO2007024473A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US11/210,181 2005-08-23
US11/210,181 US20070052660A1 (en) 2005-08-23 2005-08-23 Forming display color image

Publications (1)

Publication Number Publication Date
WO2007024473A1 true WO2007024473A1 (fr) 2007-03-01

Family

ID=37546810

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2006/030832 WO2007024473A1 (fr) 2005-08-23 2006-08-08 Formation d'image couleur sur un dispositif d'affichage

Country Status (2)

Country Link
US (1) US20070052660A1 (fr)
WO (1) WO2007024473A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009051720A1 (fr) * 2007-10-16 2009-04-23 Lucent Technologies Inc. Réduction de chatoiement à l'aide d'une lentille liquide modulable
WO2017114805A1 (fr) * 2015-12-31 2017-07-06 Amazon Technologies, Inc. Composés colorants pour un élément d'électromouillage

Families Citing this family (59)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002091319A2 (fr) * 2001-05-04 2002-11-14 Igt Affichages a interface electroluminescente pour appareil de jeux de hasard
US8342938B2 (en) 2001-09-27 2013-01-01 Igt Gaming machine reel having a rotatable dynamic display
US8002624B2 (en) * 2001-09-27 2011-08-23 Igt Gaming machine reel having a flexible dynamic display
US7417782B2 (en) 2005-02-23 2008-08-26 Pixtronix, Incorporated Methods and apparatus for spatial light modulation
US8388432B2 (en) * 2004-01-12 2013-03-05 Igt Bi-stable downloadable reel strips
US8545326B2 (en) * 2004-01-12 2013-10-01 Igt Casino display methods and devices
US8016670B2 (en) * 2004-01-12 2011-09-13 Igt Virtual glass for a gaming machine
US8482496B2 (en) 2006-01-06 2013-07-09 Pixtronix, Inc. Circuits for controlling MEMS display apparatus on a transparent substrate
US7746529B2 (en) 2005-02-23 2010-06-29 Pixtronix, Inc. MEMS display apparatus
US7742016B2 (en) * 2005-02-23 2010-06-22 Pixtronix, Incorporated Display methods and apparatus
US7999994B2 (en) 2005-02-23 2011-08-16 Pixtronix, Inc. Display apparatus and methods for manufacture thereof
US8310442B2 (en) 2005-02-23 2012-11-13 Pixtronix, Inc. Circuits for controlling display apparatus
US9158106B2 (en) 2005-02-23 2015-10-13 Pixtronix, Inc. Display methods and apparatus
US9082353B2 (en) 2010-01-05 2015-07-14 Pixtronix, Inc. Circuits for controlling display apparatus
US9229222B2 (en) 2005-02-23 2016-01-05 Pixtronix, Inc. Alignment methods in fluid-filled MEMS displays
US20070205969A1 (en) 2005-02-23 2007-09-06 Pixtronix, Incorporated Direct-view MEMS display devices and methods for generating images thereon
US8159428B2 (en) 2005-02-23 2012-04-17 Pixtronix, Inc. Display methods and apparatus
US9261694B2 (en) 2005-02-23 2016-02-16 Pixtronix, Inc. Display apparatus and methods for manufacture thereof
US8519945B2 (en) 2006-01-06 2013-08-27 Pixtronix, Inc. Circuits for controlling display apparatus
US8526096B2 (en) 2006-02-23 2013-09-03 Pixtronix, Inc. Mechanical light modulators with stressed beams
US7876489B2 (en) 2006-06-05 2011-01-25 Pixtronix, Inc. Display apparatus with optical cavities
WO2008051362A1 (fr) 2006-10-20 2008-05-02 Pixtronix, Inc. Guides de lumière et systèmes de rétroéclairage comportant des redirecteurs de lumière a densité variable
US9176318B2 (en) 2007-05-18 2015-11-03 Pixtronix, Inc. Methods for manufacturing fluid-filled MEMS displays
US7852546B2 (en) 2007-10-19 2010-12-14 Pixtronix, Inc. Spacers for maintaining display apparatus alignment
US8624968B1 (en) * 2007-04-25 2014-01-07 Stc.Unm Lens-less digital microscope
US9106056B1 (en) 2007-04-25 2015-08-11 Stc.Unm Phase-coupled arrays of nanowire laser devices and method of controlling an array of such devices
US8964020B2 (en) * 2007-04-25 2015-02-24 Stc.Unm Solid-state microscope for selectively imaging a sample
JP5219493B2 (ja) * 2007-11-14 2013-06-26 キヤノン株式会社 発光素子及びそれを用いた発光装置
KR101187791B1 (ko) * 2007-12-07 2012-10-05 삼성전자주식회사 프린트 헤드 및 이를 채용한 화상형성장치
US8248560B2 (en) 2008-04-18 2012-08-21 Pixtronix, Inc. Light guides and backlight systems incorporating prismatic structures and light redirectors
JP2011518412A (ja) * 2008-04-17 2011-06-23 コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ 光影響要素を備える高い量子効率の照明装置
US8520285B2 (en) 2008-08-04 2013-08-27 Pixtronix, Inc. Methods for manufacturing cold seal fluid-filled display apparatus
US8169679B2 (en) 2008-10-27 2012-05-01 Pixtronix, Inc. MEMS anchors
GB2466846A (en) * 2009-01-13 2010-07-14 Barco Nv Sensor system and method for detecting a property of light emitted from at least one display area of a display device
TWI482214B (zh) * 2009-01-21 2015-04-21 Univ Nat Chunghsing Method for manufacturing epitaxial substrate with low surface defect density
US20130223846A1 (en) 2009-02-17 2013-08-29 Trilumina Corporation High speed free-space optical communications
US8995493B2 (en) 2009-02-17 2015-03-31 Trilumina Corp. Microlenses for multibeam arrays of optoelectronic devices for high frequency operation
US8613536B2 (en) * 2009-12-19 2013-12-24 Trilumina Corporation System and method for combining laser arrays for digital outputs
US10244181B2 (en) 2009-02-17 2019-03-26 Trilumina Corp. Compact multi-zone infrared laser illuminator
US8995485B2 (en) 2009-02-17 2015-03-31 Trilumina Corp. High brightness pulsed VCSEL sources
US10038304B2 (en) 2009-02-17 2018-07-31 Trilumina Corp. Laser arrays for variable optical properties
US8979338B2 (en) 2009-12-19 2015-03-17 Trilumina Corp. System for combining laser array outputs into a single beam carrying digital data
WO2011097258A1 (fr) 2010-02-02 2011-08-11 Pixtronix, Inc. Circuits pour commander un appareil d'affichage
US20120019713A1 (en) * 2010-07-26 2012-01-26 Qualcomm Mems Technologies, Inc. Mems-based aperture and shutter
US9140900B2 (en) 2011-07-20 2015-09-22 Pixtronix, Inc. Displays having self-aligned apertures and methods of making the same
US11095365B2 (en) 2011-08-26 2021-08-17 Lumentum Operations Llc Wide-angle illuminator module
US9134552B2 (en) 2013-03-13 2015-09-15 Pixtronix, Inc. Display apparatus with narrow gap electrostatic actuators
EP2887411A1 (fr) * 2013-12-23 2015-06-24 Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO Matériaux biréfringents photoactifs dans des OLED
KR20180030878A (ko) * 2015-07-17 2018-03-26 에이비엘 아이피 홀딩, 엘엘씨 소프트웨어 구성가능한 라이팅 디바이스
EP3325401A1 (fr) 2015-07-17 2018-05-30 ABL IP Holding LLC Systèmes et procédés permettant de fournir des données de configuration à un dispositif d'éclairage pouvant être configuré par logiciel
US10483489B2 (en) * 2016-08-12 2019-11-19 Universal Display Corporation Integrated circular polarizer and permeation barrier for flexible OLEDs
CN106952941B (zh) * 2017-05-26 2020-10-09 上海天马有机发光显示技术有限公司 一种显示面板、制作方法及电子设备
US10852532B2 (en) 2018-11-21 2020-12-01 Microsoft Technology Licensing, Llc VCSEL array scanning display
US11022826B2 (en) * 2019-07-12 2021-06-01 Massachusetts Institute Of Technology All-optical spatial light modulators
CN114868079A (zh) 2020-02-07 2022-08-05 伊英克公司 具有薄膜上电极的电泳显示层
CN111258054A (zh) 2020-03-30 2020-06-09 深圳市华星光电半导体显示技术有限公司 一种量子点显示装置及其制造方法
WO2022102678A1 (fr) * 2020-11-13 2022-05-19 京セラ株式会社 Dispositif d'affichage à cristaux liquides
CN112736214B (zh) * 2021-01-19 2022-05-31 Tcl华星光电技术有限公司 发光层的制备方法及显示面板
CN116206558B (zh) * 2023-05-06 2023-08-04 惠科股份有限公司 显示面板的控制方法及显示装置

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4938571A (en) * 1987-06-18 1990-07-03 Cogan Stuart F Solid state electrochromic light modulator
US6144361A (en) * 1998-09-16 2000-11-07 International Business Machines Corporation Transmissive electrophoretic display with vertical electrodes
US6243148B1 (en) * 1996-07-11 2001-06-05 Seiko Epson Corporation Liquid crystal display device having a two-dimensional light emitting element array
GB2357589A (en) * 1999-12-20 2001-06-27 Univ Exeter Dye doped liquid crystal device
WO2004077124A1 (fr) * 2003-02-26 2004-09-10 Koninklijke Philips Electronics N.V. Dispositif a matrice passive a cellules d'electromouillage bistables
US20050062903A1 (en) * 2003-09-23 2005-03-24 Eastman Kodak Company Organic laser and liquid crystal display

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6057906A (en) * 1996-03-29 2000-05-02 Kabushiki Kaisha Toshiba Liquid crystal display element
US6221543B1 (en) * 1999-05-14 2001-04-24 3M Innovatives Properties Process for making active substrates for color displays
US6950454B2 (en) * 2003-03-24 2005-09-27 Eastman Kodak Company Electronic imaging system using organic laser array illuminating an area light valve
JP4145227B2 (ja) * 2003-09-30 2008-09-03 富士フイルム株式会社 表示素子

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4938571A (en) * 1987-06-18 1990-07-03 Cogan Stuart F Solid state electrochromic light modulator
US6243148B1 (en) * 1996-07-11 2001-06-05 Seiko Epson Corporation Liquid crystal display device having a two-dimensional light emitting element array
US6144361A (en) * 1998-09-16 2000-11-07 International Business Machines Corporation Transmissive electrophoretic display with vertical electrodes
GB2357589A (en) * 1999-12-20 2001-06-27 Univ Exeter Dye doped liquid crystal device
WO2004077124A1 (fr) * 2003-02-26 2004-09-10 Koninklijke Philips Electronics N.V. Dispositif a matrice passive a cellules d'electromouillage bistables
US20050062903A1 (en) * 2003-09-23 2005-03-24 Eastman Kodak Company Organic laser and liquid crystal display

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
ANONYMOUS: "Gray-levels in a roll blind display", IP.COM JOURNAL, IP.COM INC., WEST HENRIETTA, NY, US, 30 August 2004 (2004-08-30), XP013021281, ISSN: 1533-0001 *
YI-PAI HUANG ET AL: "Full-color transflective cholesteric LCD with image-enhanced reflector", JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY, SOCIETY FOR INFORMATION DISPLAY, SAN JOSE, US, vol. 12, no. 4, 2004, pages 417 - 422, XP002400212, ISSN: 1071-0922 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009051720A1 (fr) * 2007-10-16 2009-04-23 Lucent Technologies Inc. Réduction de chatoiement à l'aide d'une lentille liquide modulable
US7862183B2 (en) 2007-10-16 2011-01-04 Alcatel-Lucent Usa Inc. Speckle reduction using a tunable liquid lens
WO2017114805A1 (fr) * 2015-12-31 2017-07-06 Amazon Technologies, Inc. Composés colorants pour un élément d'électromouillage
US9885863B2 (en) 2015-12-31 2018-02-06 Amazon Technologies, Inc. Dye compounds for an electrowetting element

Also Published As

Publication number Publication date
US20070052660A1 (en) 2007-03-08

Similar Documents

Publication Publication Date Title
WO2007024473A1 (fr) Formation d'image couleur sur un dispositif d'affichage
WO2005119352A1 (fr) Dispositif d'affichage utilisant des reseaux de lasers a cavite verticale
US7045825B2 (en) Vertical cavity laser producing different color light
EP1754103A1 (fr) Dispositifs d'affichage a vision directe faisant appel a des systemes laser a cavite verticale
US7292614B2 (en) Organic laser and liquid crystal display
JP4638965B2 (ja) 広帯域反射型表示器
KR100247231B1 (ko) 가변 굴절률 분포 미러
US11320690B2 (en) Color filter substrate and method of manufacturing the same, liquid crystal display panel, and liquid crystal display apparatus
US20060291769A1 (en) Light emitting source incorporating vertical cavity lasers and other MEMS devices within an electro-optical addressing architecture
JP2001509281A (ja) 相転移式フラットパネル表示装置
US8502759B2 (en) Light modulation element, driving method and drive apparatus
CN110646980B (zh) 一种液晶显示器
US20030058385A1 (en) Liquid crystal display device
US10935852B2 (en) Display panel and display device
JPS60159823A (ja) カラ−液晶表示装置
KR20070020471A (ko) 다양한 유색광 생성용 수직공진 레이저
EP1494326A1 (fr) Méthode de fabrication d'un réseau de lasers organiques à cavités verticales, le réseau comprenant un empilement diélectrique avec zone gravée
KR100224935B1 (ko) 액정표시소자
Fontecchio et al. Multiplexed holographic polymer dispersed liquid crystals
KR20070031329A (ko) 수직공동 레이저 어레이를 사용하는 직시형 디스플레이디바이스
EP1649569A1 (fr) Reseau a pompage optique de vcsel organiques
DE602004010523T2 (de) Organische Vertical-Cavity-Laser-Array-Vorrichtung
JPH0690376B2 (ja) カラー液晶表示装置
CN117539104A (zh) 一种液晶光栅及显示装置
Saitoh et al. 22.2: RGB‐Stacked Holographic Polymer Dispersed Liquid Crystal Device for Color Reflective Display

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 06800932

Country of ref document: EP

Kind code of ref document: A1